Circulating Anti-Nuclear Antibodies in Systemic Sclerosis: Utility in Diagnosis and Disease Subsetting

Precision Medicine in Rheumatology: The Role of Biomarkers in Diagnosis and Treatment Optimization

Rheumatic diseases encompass a wide range of autoimmune and inflammatory disorders, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), psoriatic arthritis (PsA), and systemic sclerosis (SSc). These conditions often result in chronic pain, disability, and reduced quality of life, with unpredictable disease courses that may lead to joint destruction, organ damage, or systemic complications. Biomarkers, defined as measurable indicators of biological processes or conditions, have the potential to transform clinical practice by improving disease diagnosis, monitoring, prognosis, and treatment decisions. While significant strides have been made in identifying and validating biomarkers in rheumatic diseases, challenges remain in their standardization, clinical utility, and integration into routine practice. This review provides an overview of the current state of biomarkers in rheumatic diseases, their roles in clinical settings, and the emerging advancements in the field.

Immunogenetics of Systemic Sclerosis

Systemic sclerosis (SSc) is a rare autoimmune connective tissue disorder characterized by massive fibrosis, vascular damage, and immune imbalance. Advances in rheumatology and immunology over the past two decades have led to a redefinition of systemic sclerosis, shifting from its initial perception as primarily a "hyperfibrotic" state towards a recognition of systemic sclerosis as an immune-mediated disease. Consequently, the search for genetic markers has transitioned from focusing on fibrotic mechanisms to exploring immune regulatory pathways. Immunogenetics, an emerging field at the intersection of immunology, molecular biology, and genetics has provided valuable insights into inherited factors that influence immunity. Data from genetic studies conducted thus far indicate that alterations in genetic messages can significantly impact disease risk and progression. While certain genetic variations may confer protective effects, others may exacerbate disease susceptibility. This paper presents a comprehensive review of the most relevant genetic changes that influence both the risk and course of systemic sclerosis. Special emphasis is placed on factors regulating the immune response, recognizing their pivotal role in the pathogenesis of the disease.

Prognostic value of anti-IFI16 autoantibodies in pulmonary arterial hypertension and mortality in patients with systemic sclerosis

OBJECTIVES

To determine the diagnostic value of anti-interferon gamma inducible protein 16 (IFI16) autoantibodies in systemic sclerosis (SSc) patients negative for all tested SSc-specific autoantibodies (SSc-seronegative patients) and to evaluate the clinical significance of these autoantibodies, whether isolated or in the presence of anti-centromere autoantibodies (ACA).

METHODS

Overall, 58 SSc-seronegative and 66 ACA-positive patients were included in the study. All patients were tested for anti-IFI16 autoantibodies by an in-house direct ELISA. Associations between clinical parameters and anti-IFI16 autoantibodies were analysed.

RESULTS

Overall, 17.2% of SSc-seronegative and 39.4% of ACA-positive patients were positive for anti-IFI16 autoantibodies. Anti-IFI16 autoantibodies were found only in patients within the limited cutaneous SSc (lcSSc) subset. A positive association between anti-IFI16 positivity and isolated pulmonary arterial hypertension (PAH) was found (odds ratio [OR]=5.07; p=0.014) even after adjusting for ACA status (OR=4.99; p=0.019). Anti-IFI16-positive patients were found to have poorer overall survival than negative patients (p=0.032). Cumulative survival rates at 10, 20 and 30 years were 96.9%, 92.5% and 68.7% for anti-IFI16-positive patients vs. 98.8%, 97.0% and 90.3% for anti-IFI16-negative-patients, respectively. Anti-IFI16-positive patients also had worse overall survival than anti-IFI16-negative patients after adjusting for ACA status in the multivariate Cox analysis (hazard ratio [HR]=3.21; p=0.043).

CONCLUSION

Anti-IFI16 autoantibodies were associated with isolated PAH and poorer overall survival. Anti-IFI16 autoantibodies could be used as a supplementary marker of lcSSc in SSc-seronegative patients and for identifying ACA-positive patients with worse clinical outcome.

Comprehensive Exploration of Antinuclear Antibodies (ANAs): Unveiling Clinical Significance, Associations with Cancer, and the Nuances of Differential Diagnosis in Positive ANA Patients

This comprehensive review delves into the complex realm of antinuclear antibodies (ANAs), expanding beyond their traditional involvement in autoimmune rheumatic disorders. By digging into historical changes, diagnostic complexity, and clinical significance, the debate reveals the shifting relationships between ANAs, particularly with cancer. Specialized studies provide practical insights on ANA testing processes, standardization, and upcoming challenges. Examining prevalence trends in the United States provides a time dimension to ANA dynamics, linking autoimmune and oncological considerations. The debate delves into the complexity of lupus erythematosus, emphasizing ANAs' diverse presentations and their potential as flexible diagnostic and prognostic indicators. The complex relationship between ANAs and cancer is highlighted, demonstrating their potential as early markers or indicators of malignancies. Looking ahead, this synthesis anticipates advances in personalized medicine and collaborative research, putting ANAs at the forefront of advanced diagnostics and treatments for autoimmune disorders and cancer. This synthesis envisions a future for ANA research in which these antibodies play a critical role in promoting personalized treatment, enhancing diagnostics, and fostering collaborative initiatives that cross traditional boundaries. As ANAs grow more prominent at the junction of autoimmune illnesses and cancer, this synthesis lays the path for further research and novel advances in understanding, diagnosing, and treating complicated medical conditions.

Systemic sclerosis patients with negative antinuclear antibodies have distinctive clinical manifestations: a multicenter CRDC cohort in China

BACKGROUND

The presence of circulating antinuclear antibodies (ANAs) is a hallmark of immune dysregulation in patients with systemic sclerosis (SSc).

OBJECTIVE

A variety of ANAs are associated with unique sets of disease manifestations and are widely used in clinical practice in SSc. This study aimed to investigate the clinical features of SSc patients negative for ANAs in a Chinese Rheumatism Data Center (CRDC) multicenter cohort in China.

METHODS

Patients were prospectively recruited between April 2008 and June 2019 from 154 clinical centers nationwide, and all cases fulfilled the 2013 ACR/EULAR classification criteria for systemic sclerosis. Results for antinuclear antibodies were intensively collected. Demographic, clinical, and laboratory data were compared between ANA-positive SSc patients and those negative for ANAs.

RESULTS

Antinuclear antibodies were detected in 2129 of 2809 patients enrolled in the study; 4.2% of patients were negative. There were more males among ANA-negative SSc patients (29/60 vs. 294/1746, p < 0.001). The incidence of certain critical organ involvement, including gastroesophageal reflux (5.6% vs. 18.5%, p = 0.002), interstitial lung disease (65.2% vs. 77.9%, p = 0.015), and pulmonary arterial hypertension (11.5% vs. 29.0%, p = 0.006) was significantly lower in ANA-negative patients than in ANA-positive patients. The proportion of abnormal erythrocyte sedimentation rate (32.4% vs. 47.6%, p = 0.013) and IgG elevation (14.3% vs. 37.0%, p = 0.003), an indicator of disease activity, was significantly lower in ANA-negative patients than in ANA-positive patients.

CONCLUSION

Antinuclear antibodies are strongly associated with the clinical manifestations of systemic sclerosis, with ANA-negative SSc patients tending to exhibit relatively milder disease.

A Historic Cohort Analysis of Radiographic and Serologic Findings in Patients With Scleroderma and Interstitial Lung Disease

BACKGROUND/OBJECTIVE

Few studies have investigated associations between rheumatologic serology patterns and different interstitial lung disease (ILD) patterns.

METHODS

We present novel findings of a historic cohort study (n = 454) with data collected from 2011 to 2021 within our hospital system. In this institutional review board-approved study, data regarding rheumatologic serologies and ILD patterns were noted based on chart review in patients with scleroderma. The Kruskal-Wallis rank sum and χ2 tests were used for statistical analysis.

RESULTS

Results showed a statistically significant association between anti-U1 snRNP with lymphoid interstitial pneumonia, which has not been previously described.

CONCLUSIONS

We demonstrated novel serologic associations with ILD patterns, which have important clinical implications. More robust and high-powered studies are needed to elucidate the role of serologic testing and their association with ILD phenotypes.

Clinical and serological correlation of systemic sclerosis in Moroccan patients

Objective

SSc is a CTD characterized by excessive fibrosis of the skin and internal organs, along with microvascular damage, and is often associated with typical autoantibodies. The aim of this study was to analyse the correlation between specific autoantibody profiles, clinical and paraclinical features in Moroccan patients with SSc.

Methods

We analysed the presence of specific autoantibodies in 46 SSc patients using IIF on HEp-2 cells and immunodot. We then correlated the types of autoantibodies with clinical and laboratory manifestations.

Results

Among our patients, 86.9% were females. The mean age of patients at diagnosis was 50.21 years, with an average delay to diagnosis of 5 years. The main clinical manifestations found were RP (89.2%), sclerodactyly (84.8%), proximal scleroderma (67.4%), gastrointestinal involvement (50%) and interstitial lung disease (30.4%). According to the specific autoantibody profile, 14 patients were anti-topo I positive (30.4%), 8 anti-RNP (68 kDa/A/C) positive (17.4%) and 6 anti-RNA polymerase III positive (13%). We found a significant association of anti-RNA polymerase III with sclerodactyly and pulmonary arterial hypertension (P < 0.05). We also found an association between anti-topo I and interstitial lung disease in 30.4% of patients. There was no significant association between the positivity for the autoantibodies and other diagnosed clinical manifestations.

Conclusion

Some clinical manifestations of SSc might be positively correlated with the presence of specific autoantibodies. Environmental factors, ethnicity and gene interaction might also influence this correlation.

Clinical assessment of patients with systemic sclerosis: is there a place for thermography?

Recurrent changes of temperature and persistence of cooling along fingers at the room temperature make hands the most frequent region of interest for thermography in systemic sclerosis (SSc). The aim of this study was to evaluate dependance of temperature in hands on a subtype of the disease, immune profile of antinuclear antibodies (ANA), and lung involvement. There were 29 patients with limited cutaneous involvement (lcSSc) and 10 patients with diffuse cutaneous disease (dcSSc) enrolled for the study. To compare measurements to normal values, there were enrolled 29 healthy volunteers (control group). All participants were submitted to thermography with handheld camera FLIR One Pro for iOS, attached to mobile phone iPhone 11, at the fixed temperature of 21 °C. Measurements included average temperature (T_avg) over nailfolds in thumbs and fingers II-V, as well as the difference in average temperatures (TΔ) between metacarpus of the hand and its thumb and fingers II-V. Both thumbs and fingers II-V remained cooler in subjects with dcSSc compared to those with lcSSc. This implicated a significantly greater TΔ along thumbs and fingers II-V in dcSSc group. Although T_avg at nailfolds in SSc patients was not lower than in healthy controls, TΔ remained significantly more pronounced in both lcSSc and dcSSc subjects. A positivity to ACA in lcSSc group was found to be associated with significantly lower T_avg and more pronounced TΔ in fingers II-V than the presence of anti-Scl70 antibodies. Temperature measurements remained statistically independent on a presence of ILD in lcSSc group, but both thumbs and fingers II-V in dcSSc group were warmer in case of lung involvement. The study showed the dcSSc subtype, the positivity of ACA in lcSSc, but not lung involvement were associated with poorer thermal control in the hands of SSc patients. A comparison to healthy controls highlighted the weakness of temperature measurements at nailfolds (T_avg) but increased the value of TΔ in thermography of hands.

Approach to Systemic Sclerosis Patient Assessment

Systemic sclerosis (SSc) is a heterogeneous disease comprising of a wide spectrum of ages of onset, sex-based differences, ethnic variations, disease manifestations, differential serologic profiles, and variable response to therapy resulting in reduced health-related quality of life, disability, and survival. The ability to subset groups of patients with SSc can assist with refining the diagnosis, guide appropriate monitoring, inform aggressiveness of immunosuppression, and predict prognosis. The ability to subset patients with SSc has several important practical implications for patient care.

Centromere defects, chromosome instability, and cGAS-STING activation in systemic sclerosis

Centromere defects in Systemic Sclerosis (SSc) have remained unexplored despite the fact that many centromere proteins were discovered in patients with SSc. Here we report that lesion skin fibroblasts from SSc patients show marked alterations in centromeric DNA. SSc fibroblasts also show DNA damage, abnormal chromosome segregation, aneuploidy (only in diffuse cutaneous (dcSSc)) and micronuclei (in all types of SSc), some of which lose centromere identity while retaining centromere DNA sequences. Strikingly, we find cytoplasmic "leaking" of centromere proteins in limited cutaneous SSc (lcSSc) fibroblasts. Cytoplasmic centromere proteins co-localize with antigen presenting MHC Class II molecules, which correlate precisely with the presence of anti-centromere antibodies. CENPA expression and micronuclei formation correlate highly with activation of the cGAS-STING/IFN-β pathway as well as markers of reactive oxygen species (ROS) and fibrosis, ultimately suggesting a link between centromere alterations, chromosome instability, SSc autoimmunity, and fibrosis.

Severe digital ischemia as an unrecognized manifestation in patients with antisynthetase autoantibodies: Case series and systematic literature review

Objective

Severe digital ischemia, including digital ulcers and gangrene, is considered rare in patients with antisynthetase antibodies. This study aimed to elucidate the clinical features of antisynthetase-positive patients complicated with digital ulcers and/or gangrene using a systematic literature review and case series in a single-center cohort.

Methods

A systematic literature review was conducted to identify reports describing antisynthetase-positive cases with digital ulcers and/or gangrene. Our cohort of consecutive patients with antisynthetase antibodies was stratified by the history of severe digital ischemia. Demographic and clinical features and outcomes in patients with severe digital ischemia identified in the systematic literature review and our cohort were compared with those in patients without severe digital ischemia in our cohort.

Results

The systematic literature review revealed 12 antisynthetase-positive patients with severe digital ischemia from one case series and eight case reports. Seven (7%) of 100 patients with antisynthetase antibodies in our cohort had a record of severe digital ischemia. Severe digital ischemia was often found at presentation and was associated with the classification of systemic sclerosis with or without myositis overlap. Clinical features associated with severe digital ischemia in antisynthetase-positive patients included Raynaud's phenomenon (p < 0.001), digital pitting scars (p = 0.001), and nailfold capillary abnormality (p = 0.02). Outcomes of severe digital ischemia were generally favorable with vasodilators.

Conclusion

Severe digital ischemia is an overlooked complication in antisynthetase-positive patients. Antisynthetase antibodies should be measured in patients presenting with digital ulcers or gangrene, especially in those with systemic sclerosis phenotype and features associated with antisynthetase antibodies in the absence of systemic sclerosis-specific autoantibodies.

A cell-based assay for detection of anti-fibrillarin autoantibodies with performance equivalent to immunoprecipitation

Anti-fibrillarin autoantibodies are useful for the diagnosis and prognosis of systemic sclerosis (SSc). Anti-fibrillarin produces a clumpy nucleolar pattern in indirect immunofluorescence assay on HEp-2 cells (HEp-2 IFA). Here we develop and validate a reliable cell-based anti-fibrillarin assay (Fibrillarin/CBA) for use in clinical diagnostic laboratories. A TransMembrane Signal was fused to the human fibrillarin gene (TMS-fibrillarin). HEp-2 cells overexpressing transgenic TMS-fibrillarin at the cytoplasmic membrane were used as IFA substrate in the Fibrillarin/CBA. Sixty-two serum samples with nucleolar pattern in the HEp-2 IFA (41 clumpy; 21 homogeneous/punctate) were tested for anti-fibrillarin using Fibrillarin/CBA, immunoprecipitation (IP), line-blot and ELISA. In addition, samples from 106 SSc-patients were evaluated with Fibrillarin/CBA and the results were correlated with disease phenotypes. Thirty-eight of 41 samples with the clumpy nucleolar pattern (92.7%) were positive in the Fibrillarin/CBA, while all 21 samples with other nucleolar patterns were negative. Fibrillarin/CBA results agreed 100% with IP results. Among the 38 Fibrillarin/CBA-positive samples, only 15 (39.5%) and 11 (29%) were positive for anti-fibrillarin in line-blot and ELISA, respectively. Higher frequency of diffuse cutaneous SSc (dcSSc) phenotype (72.7% vs 36.8%; p=0.022), cardiac involvement (36.4% vs 6.5%; p=0.001) and scleroderma renal crisis (18.2% vs 3.3% p = 0.028) was observed in SSc patients with positive compared to negative Fibrillarin/CBA result. Performance of Fibrillarin/CBA in the detection of anti-fibrillarin autoantibodies was comparable to the gold standard IP. Positive Fibrillarin/CBA results correlated with disease phenotypes known to be associated with anti-fibrillarin autoantibodies, underscoring the clinical validation of this novel assay.

Outcomes in patients with systemic sclerosis undergoing early versus delayed intervention with potential disease-modifying therapies

OBJECTIVE

To examine whether early therapeutic intervention, compared with delayed intervention, is beneficial for patients with early systemic sclerosis (SSc).

METHODS

This is a single-center, retrospective cohort study of SSc patients who received cyclophosphamide, mycophenolate mofetil, methotrexate, or tocilizumab for diffuse cutaneous SSc (dcSSc) or interstitial lung disease (ILD) within 6 years after disease onset. The patients were divided into early and delayed intervention groups based on the disease duration of ≤ 18 and >18 months at treatment introduction, respectively. Clinical worsening was defined as the development of any original or revised ACR Composite Response Index in Systemic Sclerosis (CRISS) step 1 event or progressive fibrosing ILD (PF-ILD).

RESULTS

There was no difference in baseline characteristics between the early (n = 25) and delayed (n = 21) intervention groups except forced vital capacity (FVC), which was better in the early vs delayed intervention groups. The early intervention group less frequently had stable pulmonary function over one year than did the late intervention group (odds ratio 0.087, 95% confidence interval 0.0079-0.51, p = 0.003). The active disease was significantly decreased from 79% to 42% in the early intervention group (p = 0.007), but the change in the delayed intervention group was not statistically significant (68% to 42%, p = 0.11). Cumulative rates free from clinical worsening events defined by revised ACR-CRISS and PF-ILD were significantly higher in the early vs delayed intervention groups (p = 0.03 and 0.003, respectively).

CONCLUSION

A therapeutic "window of opportunity" might exist in SSc patients.

Role of Vitamin D in Systemic Sclerosis: A Systematic Literature Review

Background

Systemic sclerosis (SSc) is a chronic multisystem autoimmune condition defined by a complex pathobiology, comprising excessive fibrosis of skin and internal organs, peripheral vasculopathy with endothelial cell dysfunction, inadequate vascular repair and neovascularization, and aberrant immunity. Vitamin D is a steroid hormone with pleiotropic effects beyond its traditional role in calcium and bone homeostasis. Since vitamin D has immunomodulatory, cardioprotective, and antifibrotic properties, it could potentially interfere with SSc pathogenesis. Suboptimal vitamin D levels are classically recognized in scleroderma, irrespective of clinical and serological phenotype.

Aim

This systematic review is aimed at investigating and clarifying the role of vitamin D in SSc and emphasizing the association of vitamin D status with different clinical settings.

Methods and Results

A systematic online search was performed, using PubMed databases to collect articles on the topic of vitamin D in SSc. The final analysis included 40 eligible articles.

Conclusions

Hypovitaminosis D is common in SSc patients and could be associated with clinical and serologic patterns of the disease. Intervention for low serum vitamin D levels in SSc pathogenesis remains controversial, as well as the significance of vitamin D supplementation in such patients.

Clinical Relevance of the Serial Measurement of Krebs von den Lungen-6 Levels in Patients with Systemic Sclerosis-Associated Interstitial Lung Disease

Krebs von den Lungen-6 (KL-6) levels measured at baseline have been reported as a circulating biomarker useful for the detection, evaluation of severity and assessment of risk of the progression of interstitial lung disease (ILD) in patients with systemic sclerosis (SSc). In this retrospective study, longitudinal changes in serum KL-6 levels over 2 years were examined in 110 patients with SSc using prospectively collected cohort data. Serum KL-6 levels fluctuated in a significant proportion of the patients but remained stable in the remaining patients. A wide range of variability of longitudinal KL-6 levels was associated with the presence of ILD, diffuse cutaneous SSc, positive anti-topoisomerase I antibodies, negative anticentromere antibodies, increased ILD extent on high-resolution computed tomography, extensive disease, low pulmonary function parameters, high KL-6 levels at baseline and immunomodulatory treatment. Extensive disease was consistently identified as an independent factor associated with variability in KL-6 levels in different models of multiple regression analysis. We failed to demonstrate correlations between trends for KL-6 level changes during the 6 months after SSc diagnosis and ILD progression over 2 years in patients with SSc-ILD. Serum KL-6 levels fluctuate in SSc patients with ILD, especially in those with extensive disease, but the clinical utility of a serial KL-6 level measurement remains uncertain.

Nintedanib in patients with systemic sclerosis-associated interstitial lung disease: subgroup analyses by autoantibody status and skin score

Objective

Using data from the SENSCIS trial, these analyses were undertaken to assess the effects of nintedanib versus placebo in subgroups of patients with systemic sclerosis–associated interstitial lung disease (SSc‐ILD), based on characteristics previously identified as being associated with the progression of SSc‐ILD.

Methods

Patients with SSc‐ILD were randomized to receive either nintedanib or placebo, stratified by anti–topoisomerase I antibody (ATA) status. We assessed the rate of decline in forced vital capacity (FVC) (expressed in ml/year) over 52 weeks in subgroups based on baseline ATA status, modified Rodnan skin thickness score (MRSS) (<18 versus ≥18), and SSc subtype (limited cutaneous SSc [lcSSc] versus diffuse cutaneous SSc [dcSSc]).

Results

At baseline, 60.8% of 576 patients who received treatment with either nintedanib or placebo were positive for ATA, 51.9% had dcSSc, and 77.5% of 574 patients with MRSS data available had an MRSS of <18. The effect of nintedanib versus placebo on reducing the rate of decline in FVC (ml/year) was numerically more pronounced in ATA‐negative patients compared to ATA‐positive patients (adjusted difference in the rate of FVC decline, 57.2 ml/year [95% confidence interval (95% CI) –3.5, 118.0] versus 29.9 ml/year [95% CI –19.1, 78.8]), in patients with a baseline MRSS ≥18 compared to those with a baseline MRSS of <18 (adjusted difference in the rate of FVC decline, 88.7 ml/year [95% CI 7.7, 169.8] versus 26.4 ml/year [95% CI –16.8, 69.6]), and in patients with dcSSc compared to those with lcSSc (adjusted difference in the rate of FVC decline, 56.6 ml/year [95% CI 3.2, 110.0] versus 25.3 ml/year [95% CI –28.9, 79.6]). However, all exploratory interaction P values were nonsignificant (all P > 0.05), indicating that there was no heterogeneity in the effect of nintedanib versus placebo between these subgroups of patients.

Conclusion

In patients with SSc‐ILD, reduction in the annual rate of decline in FVC among patients receiving nintedanib compared to those receiving placebo was not found to be heterogenous across subgroups based on ATA status, MRSS, or SSc subtype.

Video Abstract

Role of autoantibodies in the diagnosis and prognosis of interstitial lung disease in autoimmune rheumatic disorders

Interstitial lung disease (ILD) has been recognized as a frequent manifestation associated with a substantial morbidity and mortality burden in patients with autoimmune rheumatic disorders. Serum autoantibodies are considered good biomarkers for identifying several subsets or specific phenotypes of ILD involvement in these patients. This review features the role of several autoantibodies as a diagnostic and prognostic biomarker linked to the presence ILD and specific ILD phenotypes in autoimmune rheumatic disorders. The case of the diverse antisynthetase antibodies in the antisynthease syndrome or the anti-melanoma differentiation-associated 5 protein (MDA5) antibodies as a marker of a severe condition such as rapidly progressive ILD in patients with clinically amyopathic dermatomyositis are some of the associations herein reported in the group of myositis spectrum disorders. Specific autoantibodies such as the well-known anti-topoisomerase I (anti-Scl70) or the anti-Th/To, anti-U11/U12 ribonucleoprotein, and anti-eukaryotic initiation factor 2B (eIF2B) antibodies seems to be specifically linked to ILD in patients with systemic sclerosis. Overlap syndromes between systemic sclerosis and myositis, also have good ILD biomarkers, which are the anti-PM/Scl and anti-Ku autoantibodies. Lastly, other not so often reported disorders as being associated with ILD but recently most recognized as is the case of rheumatoid arthritis associated ILD or entities herein included in the miscellaneous disorders section, which include anti-neutrophil cytoplasmic antibody-associated interstitial lung disease, Sjögren's syndrome or the mixed connective tissue disease, are also discussed.

Dropped head in systemic sclerosis: a case based review

Dropped head syndrome is a rare disease entity characterized by severe weakness of the cervical para-spinal muscles, resulting in a chin-on-chest deformity. Systemic sclerosis is one of the causes of dropped head syndrome, but its characteristics and prognosis remain unclear due to the extreme rarity of this condition. We present a case of dropped head which occurred in systemic sclerosis. He presented with severe dropped head and relatively mild weakness of the proximal limb muscles. Serum level of creatine kinase was elevated, myopathic change was observed in electromyography, and gadolinium enhancement was found in magnetic resonance imaging of his posterior neck muscles. Anti-topoisomerase I antibody was positive, while other autoantibodies such as anti-PM/Scl and anti-Ku antibodies were negative. Since his dropped head acutely progressed, high dose of glucocorticoid therapy was initiated, which successfully improved dropped head, serum level of creatine kinase, and gadolinium enhancement in magnetic resonance imaging. Our present case and literature review suggest that dropped head occurring in systemic sclerosis can be treatable with immunosuppressive therapy. It is important to recognize this rare but treatable involvement of systemic sclerosis because early diagnosis and treatment initiation are crucial to prevent the irreversible organ damage and the significant decrease of daily activities.

Recognising the spectrum of scleromyositis: HEp-2 ANA patterns allow identification of a novel clinical subset with anti-SMN autoantibodies

Objective

To describe systemic sclerosis (SSc) with myopathy in patients without classic SSc-specific and SSc-overlap autoantibodies (aAbs), referred to as seronegative scleromyositis.

Methods

Twenty patients with seronegative scleromyositis diagnosed by expert opinion were analysed retrospectively for SSc features at myositis diagnosis and follow-up, and stratified based on HEp-2 nuclear patterns by indirect immunofluorescence (IIF) according to International Consensus of Autoantibody Patterns. Specificities were analysed by protein A−assisted immunoprecipitation. Myopathy was considered an organ involvement of SSc.

Results

SSc sine scleroderma was a frequent presentation (45%) at myositis diagnosis. Myositis was the most common first non-Raynaud manifestation of SSc (55%). Lower oesophagal dysmotility was present in 10 of 11 (91%) investigated patients. At follow-up, 80% of the patients met the American College of Rheumatology/EULAR SSc classification criteria. Two-thirds of patients had a positive HEp-2 IIF nuclear pattern (all with titers ≥1/320), defining three novel scleromyositis subsets. First, antinuclear antibody (ANA)-negative scleromyositis was associated with interstitial lung disease (ILD) and renal crisis. Second, a speckled pattern uncovered multiple rare SSc-specific aAbs. Third, the nuclear dots pattern was associated with aAbs to survival of motor neuron (SMN) complex and a novel scleromyositis subset characteriszed by calcinosis but infrequent ILD and renal crisis.

Conclusions

SSc skin involvement is often absent in early seronegative scleromyositis. ANA positivity, Raynaud phenomenon, SSc-type capillaroscopy and/or lower oesophagal dysmotility may be clues for scleromyositis. Using HEp-2 IIF patterns, three novel clinicoserological subsets of scleromyositis emerged, notably (1) ANA-negative, (2) ANA-positive with a speckled pattern and (3) ANA-positive with nuclear dots and anti-SMN aAbs.

Updates on genetics in systemic sclerosis

Systemic sclerosis (SSc) is a complex disease, in which an interaction of genetic and environmental factors plays an important role in its development and pathogenesis. A number of genetic studies, including candidate gene analysis and genome-wide association study, have found that the associated genetic variants are mainly localized in noncoding regions in the expression quantitative trait locus and influence corresponding gene expression. The gene variants identified as a risk for SSc susceptibility include those associated with innate immunity, adaptive immune response, and cell death, while there are only few SSc-associated genes involved in the fibrotic process or vascular homeostasis. Human leukocyte antigen class II genes are associated with SSc-related autoantibodies rather than SSc itself. Since the pathways between the associated genotype and phenotype are still poorly understood, further investigations using multi-omics technologies are necessary to characterize the complex molecular architecture of SSc, identify biomarkers useful to predict future outcomes and treatment responses, and discover effective drug targets.

Metabolic mediators determine the association of antinuclear antibody subtypes with specific clinical symptoms in systemic sclerosis

PURPOSE

The aim of this study was to investigate the possible link between different types of systemic sclerosis-specific antinuclear antibodies, adipokines and endothelial molecules which were recently found to have a pathogenic significance in systemic sclerosis.

MATERIALS/METHODS

Serum concentration of adiponectin, resistin, leptin, endothelin-1, fractalkine and galectin-3 were determined in the sera of patients with systemic sclerosis (n ​= ​100) and healthy controls (n ​= ​20) using ELISA.

RESULTS

The following associations between antinuclear antibodies and increased serum concentrations were identified: anticentromere antibodies with endothelin-1 (p ​< ​0.0001; mean level in patients 2.21 vs control group 1.31 ​pg/ml), anti-topoisomerase I antibodies with fractalkine (p ​< ​0.0001; 3.68 vs 1.68 ​ng/ml) and galectin-3 (p ​= ​0.0010, 6.39 vs 3.26 ​ng/ml). Anti-RNA polymerase III antibodies were associated with increased resistin (p ​< ​0.0001; 15.13 vs 8.54 ​ng/ml) and decreased adiponectin (p ​< ​0.0001; 2894 vs 8847 ​ng/ml).

CONCLUSION

In systemic sclerosis metabolic and vascular factors may serve as mediators between immunological abnormalities and non-immune driven clinical symptoms.

Clinical consequences of the presence of anti-RNA Pol III antibodies in systemic sclerosis

Introduction

Anti-RNA polymerase III (a-RNA Pol III) antibodies are marker antibodies in patients with systemic sclerosis (SSc).

Aim

To assess the prevalence of a-RNA Pol III in patients with SSc and to identify the differences in the disease picture in SSc patients with and without a-RNA Pol III antibodies.

Material and methods

The study was performed in 126 SSc patients. The subtype of SSc, incidence of internal organ involvement, malignancy, death and serological profiles were determined in the entire group. The study groups were studied according to the presence of antibodies by applying the commercial test - EUROLINE SSc Profile. Due to the presence of a-RNA Pol III, patients were divided into two groups: the a-RNA Pol III (+) SSc group of 19 patients and the a-RNA Pol III (-) SSc group of 107 patients.

Results

A-RNA Pol III were present in 19/126 patients with SSc (15%), 13/19 (68.4%) patients had no other SSc marker antibodies. A-RNA Pol III were more common in patients with diffuse cutaneous SSc (p = 0.049). We showed a significant positive association between a-RNA Pol III and occurrence of malignancy (p = 0.007), scleroderma renal crisis (p = 0.001) and decreased DLCO (p = 0.007).

Conclusions

Anti-a-RNA Pol III antibodies are common in patients with SSc, particularly with a diffuse subtype. In more than 50% of patients with a-RNA Pol III antibodies, they may be present as the sole marker of antibodies. In SSc, a-RNA Pol III antibodies are frequently associated with malignancy occurrence, kidney and lung involvement.

Biomarkers as an opportunity to stratify for outcome in systemic sclerosis

Systemic sclerosis (SSc) is a highly complex disease whose heterogeneity includes multiple aspects of the condition, such as clinical presentation, progression, extent and type of organ involvement, and clinical outcomes. Thus far, these features remain not easily predictable both at the patient group level and in a given patient with regard to age at onset and clinical course. The unpredictable clinical course represents an obstacle to focusing potentially effective treatment in patients that need it the most. At the time of organ involvement and clinical diagnosis, most of the clinical manifestations are irreversible; therefore, predicting outcomes becomes crucial. This can explain the multiple attempts to identify prognostic, predictive, and monitoring-both soluble and imaging-biomarkers over the past years. They range from the currently most used biomarkers, the autoantibodies associated with disease-specific clinical features and course, to the single recently proposed skin, lung, cardiac involvement biomarkers and to the composite scores capturing multiple aspects of the disease. This review will focus on soluble and imaging biomarkers that recently showed promising evidence for outcome stratification in patients with SSc.

Antinuclear Antibodies in Systemic Sclerosis: an Update

Systemic sclerosis is an autoimmune disease characterized by fibrosis of skin and internal organs, vasculopathy, and dysregulation of immune system. A diagnostically important feature of immunological abnormalities in systemic sclerosis is the presence of circulating antinuclear antibodies, which may be detected in 90-95% of patients with either of the four main laboratory methods: immunofluorescence, enzyme-linked immunosorbent assay, immunodiffusion, and immunoblotting. There are several antinuclear antibodies specific for systemic sclerosis. These include antibodies against topoisomerase (anti-TOPO I), kinetochore proteins (ACA), RNA polymerase enzyme (anti-RNAP III), ribonuclear proteins (anti-U11/U12 RNP, anti-U1 RNP, anti-U3 RNP) and nucleolar antigens (anti-Th/To, anti-NOR 90, anti-Ku, antiRuvBL1/2, and anti-PM/Scl). Autoantibodies specific for systemic sclerosis have been linked to distinct clinical features. Therefore, detecting a particular antibody type is important in predicting a possible organ involvement and prognosis and may have an impact on monitoring and treatment.

Micronuclei, inflammation and auto-immune disease

Auto-immune diseases (AUD) are characterized by an immune response to antigenic components of the host itself. The etiology of AUD is not well understood. The available evidence points to an interaction between genetic, epigenetic, environmental, infectious and life-style factors. AUD are more prevalent in women than in men; sex hormones play a crucial role in this sex bias. Micronuclei (MN) emerged as a new player in the induction of AUD, based on the capacity of DNA-sensors to detect self-DNA that leaks into the cytoplasm from disrupted MN and induce the cGAS-STING pathway triggering an innate auto-immune response and chronic inflammation. It was found that inflammation can induce MN and MN can induce inflammation, leading to a vicious inflammation-oxidative-DNA damage-MN-formation-chromothripsis cycle. MN originating from sex chromosome-loss may induce inflammation and AUD. We performed a systematic review of studies reporting MN in patients with systemic or organ-specific AUD. A meta-analysis was performed on lymphocyte MN in diabetes mellitus (10 studies, 457 patients/290 controls) and Behcet's disease (3 studies, 100 patients/70 controls) and for buccal MN in diabetes mellitus (11 studies, 507 patients/427 controls). A statistically significant increase in patients compared to controls was found in the meta-analyses providing an indication of an association between MN and AUD. A 36%-higher mean-MRi in buccal cells (3.8+/-0.7) was found compared to lymphocytes (2.8+/-0.7)(P = 0.01). The meta-MRi in lymphocytes and buccal cells (1.7 and 3.0 respectively) suggest that buccal cells may be more sensitive. To assess their relative sensitivity, studies with measurements from the same subjects would be desirable. It is important that future studies (i) investigate, in well-designed powered studies, the prospective association of MN-formation with AUD and (ii) explore the molecular mechanisms by which chromosome shattering in MN and the release of chromatin fragments from MN lead to the formation of auto-antibodies.

Performance evaluation of a commercial line blot assay system for detection of myositis- and systemic sclerosis-related autoantibodies

INTRODUCTION/OBJECTIVES

A line blot (LB) assay is a multi-analyte platform capable of simultaneously detecting multiple anti-nuclear antibody specificities. Here, we evaluated the performance of a commercial LB assay developed for the identification of myositis- or systemic sclerosis (SSc)-related autoantibodies (autoAbs).

METHOD

We screened 300 serum samples from patients with various connective tissue diseases using an LB assay and compared the results of myositis- or SSc-related autoAbs with those identified by RNA and protein immunoprecipitation (IP) assays or indirect immunofluorescence (IIF).

RESULTS

The IP assays revealed anti-Jo-1 Abs in 14 patients, anti-EJ Abs in 12, anti-PL-7 Abs in 8, anti-PL-12 Abs in 4, anti-Mi-2 Abs in 6, anti-SRP Abs in 8, anti-topoisomerase I Abs in 54, anti-RNA polymerase III Abs in 24, anti-U3 RNP Abs in 9, anti-Th/To Abs in 9, anti-Ku Abs in 14 and anti-hUBF Abs in 4, whereas IIF identified anti-centromere in 35. Good agreement between the IP assays and the LB assay was found only for anti-Jo-1 and anti-centromere antibodies. When a cut-off was adjusted to reconcile with the results of IP assays, the detection performance of LB assay was improved for anti-EJ, anti-PL-7, anti-PL-12, anti-SRP, anti-topoisomerase I and anti-RNA polymerase III Abs. However, the results of anti-Mi-2, anti-U3 RNP, anti-Th/To, anti-hUBF and anti-Ku Abs remained discordant between the LB assay and IP assays at all cut-off levels.

CONCLUSIONS

Detection of myositis- or SSc-related autoAbs using a commercial LB assay requires great caution since it can yield analytically false-positive or false-negative results. Key Points • A line blot (LB) assay is a multi-analyte platform capable of simultaneously detecting multiple antibodies with anti-nuclear specificities. • Detection of myositis- or systemic sclerosis-related autoantibodies using a commercial LB assay requires great caution since it can yield analytically false-positive or false-negative results.

Using Autoantibodies and Cutaneous Subset to Develop Outcome-Based Disease Classification in Systemic Sclerosis

OBJECTIVE

To describe the associations between autoantibodies, clinical presentation, and outcomes among patients with systemic sclerosis (SSc) in order to develop a novel SSc classification scheme that would incorporate both antibodies and the cutaneous disease subset as criteria.

METHODS

Demographic and clinical characteristics, including cutaneous subset, time of disease and organ complication onset, and autoantibody specificities, were determined in a cohort of SSc subjects. Survival analysis was used to assess the effect of the autoantibodies on organ disease and death.

RESULTS

The study included 1,325 subjects. Among the antibody/skin disease subsets, anticentromere antibody-positive patients with limited cutaneous SSc (lcSSc) (n = 374) had the highest 20-year survival (65.3%), lowest incidence of clinically significant pulmonary fibrosis (PF) (8.5%) and scleroderma renal crisis (SRC) (0.3%), and lowest incidence of cardiac SSc (4.9%), whereas the frequency of pulmonary hypertension (PH) was similar to the mean value in the SSc cohort overall. The anti-Scl-70+ groups of patients with lcSSc (n = 138) and patients with diffuse cutaneous SSc (dcSSc) (n = 149) had the highest incidence of clinically significant PF (86.1% and 84%, respectively, at 15 years). Anti-Scl-70+ patients with dcSSc had the lowest survival (32.4%) and the second highest incidence of cardiac SSc (12.9%) at 20 years. In contrast, in anti-Scl-70+ patients with lcSSc, other complications were rare, and these patients demonstrated the lowest incidence of PH (6.9%) and second highest survival (61.8%) at 20 years. Anti-RNA polymerase antibody-positive SSc patients (n = 147) had the highest incidence of SRC (28.1%) at 20 years. The anti-U3 RNP+ SSc group (n = 56) had the highest incidence of PH (33.8%) and cardiac SSc (13.2%) at 20 years. Among lcSSc patients with other autoantibodies (n = 295), the risk of SRC and cardiac SSc was low at 20 years (2.7% and 2.4%, respectively), while the frequencies of other outcomes were similar to the mean values in the full SSc cohort. Patients with dcSSc who were positive for other autoantibodies (n = 166) had a poor prognosis, demonstrating the second lowest survival (33.6%) and frequent organ complications.

CONCLUSION

These findings highlight the importance of autoantibodies, cutaneous subset, and disease duration when assessing morbidity and mortality in patients with SSc. Our novel classification scheme may improve disease monitoring and benefit future clinical trial designs in SSc.

Significance of the angiotensin I/angiotensin II/angiotensin-(1-7) axis in the pathogenesis of systemic sclerosis

BACKGROUND

Systemic sclerosis (SSc) is a multisystemic disease with an extensive microvasculopathy. Previously, disturbances in plasma levels of angiotensin II (Ang II) and its antagonistic angiotensin-(1-7) (Ang-(1-7)) were found in patients with SSc. Their significance in a pathogenesis of SSc stays unclear due to discrepancies of earlier studies.

OBJECTIVES

To evaluate a significance of disturbances in production pathway of angiotensins in a development of SSc.

METHODS

There were enrolled 27 patients with established SSc, 23 subjects with very early SSc and 23 healthy controls. The diagnosis of SSc was established in patients who met EULAR/ACR 2013 classification criteria. Very early SSc described patients with Raynaud's phenomenon having SSc-specific antinuclear antibodies and SSc-like abnormalities in nailfold videocapillaroscopy. Patients were submitted to evaluation of internal organ involvement and blood sampling to assay plasma levels of angiotensin I, angiotensin II and angiotensin-(1-7) with ELISA technique.

RESULTS

Plasma level of angiotensin-(1-7) was significantly reduced in both SSc group (median = 47.2 pg/mL; P < 0.001) and ones with very early SSc (median = 102.7 pg/mL; P = 0.002) when compared to healthy controls (median = 176.1 pg/mL). A tendency to higher than in control group (median = 214 pg/mL) plasma level of angiotensin I was seen in SSc group (median = 392 pg/mL; P = 0.059). Differences in plasma level of angiotensin II were insignificant between all study groups. Those disturbances produced unfavourable angiotensin-(1-7)/angiotensin II (%) ratio in both groups of patients, which achieved statistical significance in subjects with established SSc (P < 0.001). Production pathway of angiotensins showed a dependence on a subtype of SSc, immune profile and a presence of interstitial lung disease.

CONCLUSIONS

Production of angiotensin-(1-7) was significantly reduced in both SSc patients and those ones with very early SSc, although a significant imbalance between angiotensin II and angiotensin-(1-7) occurred only in subjects with established disease.

Antibodies against specific extractable nuclear antigens (ENAs) as diagnostic and prognostic tools and inducers of a profibrotic phenotype in cultured human skin fibroblasts: are they functional?

BACKGROUND

The importance of systemic sclerosis (SSc) autoantibodies for diagnosis has become recognized by their incorporation into the 2013 ACR/EULAR classification criteria. Clear prognostic and phenotypic associations with cutaneous subtype and internal organ involvement have been also described. However, little is known about the potential of autoantibodies to exert a direct pathogenic role in SSc. The aim of the study is to assess the pathogenic capacity of anti-DNA-topoisomerase I (anti-Topo-I) and anti-centromeric protein B (anti-Cenp-B) autoantibodies to induce pro-fibrotic markers in dermal fibroblasts.

METHODS

Dermal fibroblasts were isolated from unaffected and affected skin samples of (n = 10) limited cutaneous SSc (LcSSc) patients, from affected skin samples of diffuse cutaneous (DcSSc) patients (n = 10) and from healthy subjects (n = 20). Fibroblasts were stimulated with anti-Topo-I, anti-Cenp-B IgGs, and control IgGs in ratios 1:100 and 1:200 for 24 h. Cells were also incubated with 10% SSc anti-Topo-I+ and anti-Cenp-B+ whole serum and with 10% control serum for 24 h. Viability was assessed by MTT test, while apoptosis was assessed by flow cytometry. Activation of pro-fibrotic genes ACTA2, COL1A1, and TAGLN was evaluated by quantitative real-time PCR (qPCR), while the respective protein levels alpha-smooth-muscle actin (α-SMA), type-I-collagen (Col-I), and transgelin (SM22) were assessed by immunocytochemistry (ICC).

RESULTS

MTT showed that anti-Cenp-B/anti-Topo-I IgGs and anti-Cenp-B+/anti-Topo-I+ sera reduced viability (in a dilution-dependent manner for IgGs) for all the fibroblast populations. Apoptosis is induced in unaffected LcSSc and control fibroblasts, while affected LcSSc/DcSSc fibroblasts showed apoptosis resistance. Basal mRNA (ACTA2, COL1A1, and TAGLN) and protein (α-SMA, Col-1, and SM22) levels were higher in affected LcSSc/DcSSc fibroblasts compared to LcSSc unaffected and to control ones. Stimulation with anti-Cenp-B/anti-Topo-I IgGs and with anti-Cenp-B+/anti-Topo-I+ sera showed a better induction in unaffected LcSSc and control fibroblasts. However, a statistically significant increase of all pro-fibrotic markers is reported also in affected LcSSc/DcSSc fibroblasts upon stimulation with both IgGs and sera.

CONCLUSIONS

This study suggests a pathogenic role of SSc-specific autoantibodies to directly induce pro-fibrotic activation in human dermal fibroblasts. Therefore, besides the diagnostic and prognostic use of those autoantibodies, these data might further justify the importance of immunosuppressive drugs in the early stages of the autoimmune disease, including SSc.

The Impact of Autoantibodies on IVF Treatment and Outcome: A Systematic Review

The role of autoantibodies in in vitro fertilization (IVF) has been discussed for almost three decades. Nonetheless, studies are still scarce and widely controversial. The aim of this study is to provide a comprehensive systematic review on the possible complications associated to autoantibodies (AA) impeding the chances of a successful IVF cycle. An Embase, PubMed/Medline and Cochrane Central Database search was performed on 1 December 2018, from 2006 until that date. From the 598 articles yielded in the search only 44 relevant articles ultimately fulfilled the inclusion criteria and were qualitatively analyzed. Five subsets of results were identified, namely, thyroid related AA, anti-phospholipid antibodies, anti-nuclear antibodies, AA affecting the reproductive system and AA related to celiac disease. It may be implied that the majority of auto-antibodies exert a statistically significant effect on miscarriage rates, whereas the effects on clinical pregnancy and live birth rates differ according to the type of auto-antibodies. While significant research is performed in the field, the quality of evidence provided is still low. The conduction of well-designed prospective cohort studies is an absolute necessity in order to define the impact of the different types of autoantibodies on IVF outcome.

Anti-nuclear autoantibodies in systemic sclerosis : News and perspectives

Systemic sclerosis is a connective tissue disorder characterized by microvascular damage and excessive fibrosis of the skin and internal organs. One hallmark of the immunological abnormalities in systemic sclerosis is the presence of anti-nuclear antibodies, which are detected in more than 90% of patients with systemic sclerosis. Anti-centromere antibodies, anti-DNA topoisomerase I antibodies, and anti-RNA polymerase III antibodies are the predominant anti-nuclear antibodies found in systemic sclerosis patients. Other systemic sclerosis-related anti-nuclear antibodies include those targeted against U3 ribonucleoprotein, Th/To, U11/U12 ribonucleoprotein, and eukaryotic initiation factor 2B. Anti-U1 ribonucleoprotein, anti-Ku antibodies, anti-PM-Scl, and anti-RuvBL1/2 antibodies are associated with systemic sclerosis overlap syndrome. Anti-human upstream binding factor, anti-Ro52/TRIM21, anti-B23, and anti-centriole antibodies do not have specificity to systemic sclerosis, but are sometimes detected in sera from patients with systemic sclerosis. Identification of each systemic sclerosis-related antibody is useful to diagnose and predict organ involvement, since the particular type of systemic sclerosis-related antibodies is often predictive of clinical features, severity, and prognosis. The clinical phenotypes are largely influenced by ethnicity. Currently, an immunoprecipitation assay is necessary to detect most systemic sclerosis-related antibodies; therefore, the establishment of an easy, reliable, and simple screening system is warranted.

Bicaudal D2 is a novel autoantibody target in systemic sclerosis that shares a key epitope with CENP-A but has a distinct clinical phenotype

We studied the clinical correlations and epitopes of autoantibodies directed to a novel autoantigen, Bicaudal D (BICD2), in systemic sclerosis (SSc) and reviewed its relationship to centromere protein A (CENP-A). 451 SSc sera were tested for anti-BICD2 using a paramagnetic bead immunoassay and then univariate and multivariate logistic regression was used to study the association between anti-BICD2 and demographic and clinical parameters as well as other SSc-related autoantibodies. Epitope mapping was performed on solid phase matrices. 25.7% (116/451) SSc sera were anti-BICD2 positive, of which 19.0% had single specificity anti-BICD2 and 81.0% had other autoantibodies, notably anti-CENP (83/94; 88.3%). Compared to anti-BICD2 negative subjects (335/451), single specificity anti-BICD2 subjects were more likely to have an inflammatory myopathy (IM; 31.8% vs. 9.6%, p=.004) and interstitial lung disease (ILD; 52.4% vs. 29.0%, p=.024). Epitope mapping revealed a serine- and proline-rich nonapeptide SPSPGSSLP comprising amino acids 606-614 of BICD2, shared with CENP-A but not CENP-B. We observed that autoantibodies to BICD2 represent a new biomarker as they were detected in patients without other SSc-specific autoantibodies and were the second most common autoantibody identified in this SSc cohort. Our data indicate that the major cross-reactive epitope is associated with anti-CENP-A but, unlike anti-CENP, single specificity anti-BICD2 antibodies associate with ILD and IM.

Pathogenesis of systemic sclerosis: recent insights of molecular and cellular mechanisms and therapeutic opportunities

Systemic sclerosis (SSc) is a complex disease characterized by early microvascular abnormalities, immune dysregulation and chronic inflammation, and subsequent fibrosis of the skin and internal organs. Excessive fibrosis, distinguishing hallmark of SSc, is the end result of a complex series of interlinked vascular injury and immune activation, and represents a maladaptive repair process. Activated vascular, epithelial, and immune cells generate pro-fibrotic cytokines, chemokines, growth factors, lipid mediators, autoantibodies, and reactive oxygen species. These paracrine and autocrine cues in turn induce activation, differentiation, and survival of mesenchymal cells, ensuing tissue fibrosis through increased collagen synthesis, matrix deposition, tissue rigidity and remodeling, and vascular rarefaction. This review features recent insights of the pathogenic process of SSc, highlighting three major characteristics of SSc, microvasculopathy, excessive fibrosis, and immune dysregulation, and sheds new light on the understanding of molecular and cellular mechanisms contributing to the pathogenesis of SSc and providing novel avenues for targeted therapies.

Personalized medicine in rheumatology: the paradigm of serum autoantibodies

The sequencing of the human genome is now well recognized as the starting point of personalized medicine. Nonetheless, everyone is unique and can develop different phenotypes of the same disease, despite identical genotypes, as well illustrated by discordant monozygotic twins. To recognize these differences, one of the easiest and most familiar examples of biomarkers capable of identifying and predicting the outcome of patients is represented by serum autoantibodies. In this review, we will describe the concept of personalized medicine and discuss the predictive, prognostic and preventive role of antinuclear antibodies (ANA), anti-citrullinated peptide antibodies (ACPA), rare autoantibodies and anti-drug antibodies (ADA), to evaluate how these can help to identify different disease immune phenotypes and to choose the best option for treating and monitoring rheumatic patients in everyday practice. The importance of ANA resides in the prediction of clinical manifestations in systemic sclerosis and systemic lupus erythematosus and their association with malignancies. ACPA have a predictive role in rheumatoid arthritis, they are associated with the development of a more aggressive disease, extra-articular manifestations and premature mortality in RA patients; moreover, they are capable of predicting therapeutic response. Rare autoantibodies are associated with different disease manifestations and also with a greater incidence of cancer. The determination of ADA levels may be useful in patients where the clinical efficacy of TNF-α inhibitor has dropped, for the assessment of a right management. The resulting scenario supports serum autoantibodies as the cornerstone of personalized medicine in autoimmune diseases.